TAMPA, Fla. (AP) — Republicans wrapped up their "trust me" convention, sending presidential nominee Mitt Romney into the final weeks of a campaign that is long on promises and strikingly short on details.

When his wife, Ann, kicked things off by declaring "you can trust Mitt," she summed up the three-day theme, intentionally or not.

Take it on faith, the message was. Because Romney is not spelling out how he intends to restore fiscal responsibility while cutting taxes, expanding the military and standing by — for now, at least — as lawmakers from both parties jealously protect countless government programs.

Allies promised Romney will tell "hard truths" and not duck tough issues. But so far he has specified little about the pain Americans would have to accept to tame deficit spending and cure other ills he blames on President Barack Obama.

Republicans are quick to note that Obama, too, pushes ideas that fall well short of putting the government back on a track to balanced budgets in the foreseeable future, and he has not offered a plan to put entitlement programs like Medicare and Social Security on a sustainable long-term path.

But Obama has gone further than Romney, if for no other reason than presidents submit proposed budgets to Congress. Obama has proposed tax hikes — mostly on wealthier Americans — and targeted spending cuts, including a bid to trim Medicare spending by $716 billion over 10 years, in part to finance his health care law.

If Obama glosses over important details at the Democrats' convention next week, he'll open himself to the same tough scrutiny that Romney invited in Tampa.

Curiously, Republican convention speakers cast an even sharper light on Romney's stinginess with eat-your-broccoli details, by painting him as a gutsy politician unafraid to anger voters.

"Mitt Romney will tell us the hard truths we need to hear to end the torrent of debt that is compromising our future and burying our economy," New Jersey Gov. Chris Christie said in the keynote address. "Our problems are big, and the solutions will not be painless."

But who, specifically, will suffer pain, and what kind of pain? Romney has not said.

On Medicare, for instance, he calls for eventually shifting the popular-but-costly program to a voucher-like program, which almost certainly would reduce costs and benefits. But the change wouldn't start for 10 years, and by then Romney would be an ex-president, even if he wins two terms. Meanwhile, details of the benefit changes are impossible to know.

On the spending side, Romney would restore the 10-year, $716 billion in Medicare cuts, or savings, that Obama wants.

A casual TV viewer of the GOP convention might wonder why the party that calls for less government has nominated someone who wants to restore billions of dollars in spending cuts pushed by a Democratic president.

Romney is no more specific about which tax breaks, or "loopholes," he would eliminate so he can reduce tax rates without big drops in revenue. Perhaps the mortgage interest deduction? The charitable gifts deduction? The tax break for employer-provided health insurance?

"I know our Democrat friends would love to have me specify one or two so they could amass the special interests to fight that effort," Romney told Time magazine.

Indeed, such tax breaks have powerful friends with well-paid lobbyists. But so does virtually every government spending program, agency and tax quirk. That's why almost any effort to cut spending or raise revenues faces stiff, sometimes ferocious, resistance in Washington.

Having an electoral mandate helps. But that requires a nominee to campaign on a specific issue, so if he wins, he can tell the naysayers he has the voters' endorsement for change.

On the spending side, Romney promises to cut $500 billion per year by 2016 to bring spending below 20 percent of the U.S. economy. He says he will balance the budget by 2020.

Not only does he provide few specific targets for spending cuts. He also calls for big increases in military spending, along with the restored Medicare money, plus lower income tax rates.

The few specifics Romney offers include repealing Obama's health care law, cutting federal payrolls, weaning Amtrak from subsidies, trimming foreign aid and curbing the Medicaid health care program for the poor and disabled. Those steps would not get him close to his overall goals. But he's offering few other details.

"I'm going to take a lot of departments in Washington, and agencies, and combine them," Romney told Florida campaign donors in April, in remarks overhead by reporters. "Some eliminate, but I'm probably not going to lay out just exactly which ones are going to go," he said. To date, he has stuck to that strategy.

House Republican leaders routinely force the Defense Department to keep spending money on programs and weapons systems it wants to scrap. The GOP-led House recently rejected efforts to trim Pentagon spending on military bands and sponsorships for sports organization such as NASCAR.

If a debt-ridden government can't reduce spending on military musicians, critics say, how can it hope to make much deeper and more painful cuts in programs such as Medicare and Social Security?

Lawmakers defend existing programs, of course, because their constituents — the American people — want them, sometimes desperately.

Christie was right to say voters should hear "hard truths" and brace for pain if the nation is to control deficit spending. Of course, voters often reject politicians who peddle such medicine.

In a National Journal poll, three-fourths of Americans said Social Security should not be cut at all, and four-fifths said the same about Medicare.

A CBS News poll found that 45 percent of Americans say they will accept less local government if it means significantly lower taxes. As Romney and other politicians know, however, the appetite for smaller government drops as the debate becomes more specific.

Eighty percent of those polled by CBS said they would not accept fewer firefighters and police officers, for instance.

Sen. John McCain used the word "trust" seven times in his convention speech lauding Romney.

"I trust him to lead us," said McCain, who defeated Romney and others to become the party's 2008 nominee.

Romney, a well-financed candidate who has been running for president for five years, is an attractive alternative for millions of voters ready for change.

As for the sliver of undecided voters wondering exactly what he would do if elected? He asks for their trust.